Affected: pydantic-settings
pydantic-settings provides settings management using Pydantic. From 2.12.0 until 2.14.2, NestedSecretsSettingsSource reads secret values from files in a configured secrets_dir. When secrets_nested_subdir=True, a directory entry inside secrets_dir that is a symbolic link pointing outside secrets_dir is followed, so files outside the configured directory are read into settings values. The same code path bypasses the documented secrets_dir_max_size protection. An attacker or lower-privileged component able to influence entries in the configured secrets directory (for example, a writable or shared secrets mount) can turn this into an unintended local file read into settings and can defeat the advertised loading-size cap. This vulnerability is fixed in 2.14.2.
Affected: PyPI: pydantic-settings
### Summary
`NestedSecretsSettingsSource` reads secret values from files in a configured `secrets_dir`. When `secrets_nested_subdir=True`, a directory entry inside `secrets_dir` that is a symbolic link pointing **outside** `secrets_dir` is followed, so files outside the configured directory are read into settings values. The same code path bypasses the documented `secrets_dir_max_size` protection. An attacker or lower-privileged component able to influence entries in the configured secrets directory (for example, a writable or shared secrets mount) can turn this into an unintended local file read into settings and can defeat the advertised loading-size cap. This report does not claim network reachability by itself.
### Details
`NestedSecretsSettingsSource` performed two passes over `secrets_dir` using two different, inconsistent directory-traversal implementations:
* The size check in `validate_secrets_path()` used `Path.glob('**/*')`, which does **not** descend into a symbolically-linked directory. * The loader in `load_secrets()` used `glob.iglob(f'{path}/**/*', recursive=True)` followed by `read_text()`, which **does** follow symlinked directories and reads through the link target.
Because the two passes disagreed on symlinks, a symlinked directory inside `secrets_dir` whose target lives elsewhere was invisible to the size accounting (counted as 0 bytes) while still being fully read by the loader. This produces two distinct problems:
1. **Out-of-tree read (CWE-22 /…